gcse mathematics

Unit 2 Practice Paper B markscheme

Comparison of key skills specifications 2000/2002 with 2004 standardsX015461July 2004Issue 1


GCSE Mathematics (Modular)

Paper: 5MB2F_01

Paper: 5MB2F_01 7

Session: Practice Paper B

gcse mathematics

Unit 2 Practice Paper B markscheme

NOTES ON MARKING PRINCIPLES

1 Types of mark

M marks: method marks

A marks: accuracy marks

B marks: unconditional accuracy marks (independent of M marks)

2 Abbreviations

cao – correct answer only ft – follow through

isw – ignore subsequent working SC: special case

oe – or equivalent (and appropriate) dep – dependent

indep - independent

3 No working

If no working is shown then correct answers normally score full marks

If no working is shown then incorrect (even though nearly correct) answers score no marks.

4 With working

If there is a wrong answer indicated on the answer line always check the working in the body of the script (and on any diagrams), and award any marks appropriate from the mark scheme.

If working is crossed out and still legible, then it should be given any appropriate marks, as long as it has not been replaced by alternative work.

If it is clear from the working that the “correct” answer has been obtained from incorrect working, award 0 marks. Send the response to review, and discuss each of these situations with your Team Leader.

If there is no answer on the answer line then check the working for an obvious answer.

Any case of suspected misread loses A (and B) marks on that part, but can gain the M marks. Discuss each of these situations with your Team Leader.

If there is a choice of methods shown, then no marks should be awarded, unless the answer on the answer line makes clear the method that has been used.

5 Follow through marks

Follow through marks which involve a single stage calculation can be awarded without working since you can check the answer yourself, but if ambiguous do not award.

Follow through marks which involve more than one stage of calculation can only be awarded on sight of the relevant working, even if it appears obvious that there is only one way you could get the answer given.

6 Ignoring subsequent work

It is appropriate to ignore subsequent work when the additional work does not change the answer in a way that is inappropriate for the question: e.g. incorrect canceling of a fraction that would otherwise be correct

It is not appropriate to ignore subsequent work when the additional work essentially makes the answer incorrect e.g. algebra.

Transcription errors occur when candidates present a correct answer in working, and write it incorrectly on the answer line; mark the correct answer.

7 Probability

Probability answers must be given a fractions, percentages or decimals. If a candidate gives a decimal equivalent to a probability, this should be written to at least 2 decimal places (unless tenths).

Incorrect notation should lose the accuracy marks, but be awarded any implied method marks.

If a probability answer is given on the answer line using both incorrect and correct notation, award the marks.

If a probability fraction is given then cancelled incorrectly, ignore the incorrectly cancelled answer.

8 Linear equations

Full marks can be gained if the solution alone is given on the answer line, or otherwise unambiguously indicated in working (without contradiction elsewhere). Where the correct solution only is shown substituted, but not identified as the solution, the accuracy mark is lost but any method marks can be awarded.

9 Parts of questions

Unless allowed by the mark scheme, the marks allocated to one part of the question CANNOT be awarded in another.

10 Use of ranges for answers

If an answer is within a range this is inclusive, unless otherwise stated.

Question / Working / Answer / Mark / Notes
1 / (a) / Three thousand eight hundred and seven / 1 / B1 ignore spelling as long as meaning is clear
(b) / 10 215 / 1 / B1 cao
(c) / 3500 / 1 / B1 cao
(d) / 6000 / 1 / B1 accept 6 thousand or six thousand
2 / (a) / ¾ / 2 / B2 for ¾
(B1 for any fraction equivalent to ¾)
(b) / 16 squares shaded / 1 / B1 cao
3 / (a) / Line parallel to AB / 1 / B1 for line correctly drawn
(b) / Line perpendicular to PQ / 1 / B1 for line correctly drawn
4 / (i) / Sphere / 1 / B1 ignore spelling as long as meaning is clear
(ii) / Cylinder / 1 / B1 ignore spelling as long as meaning is clear
(iii) / Triangular pyramid / 1 / B1 accept pyramid
5 / = 12
= 2
20 – 14 / 6 / 3 / M1 for or 20 ÷ 5 × 3 or sight of 12
M1 for or 20 ÷ 10 or sight of 2
A1 cao
6 / (i) / 4 or 16 / 1 / B1 for either 4 or 16 or both
(ii) / 2 or 3 or 5 / 1 / B1 for 2 or 3 or 5 or any combination of the 3
(iii) / 4 and 6 / 2 / B2 for 4 and 6
(B1 for attempt to use factors of 12 as part of a summing process)
Question / Working / Answer / Mark / Notes
*7 / Loose 4 × 90p = £3.60
Small bag 2 × £1.75 = £3.50
Large bag 1 × £3.60 = £3.60 / Small bag / 3 / M2 for Loose 4 × 90p = £3.60
Small bag 2 × £1.75 = £3.50
Large bag 1 × £3.60 = £3.60
(M1 for attempt to find cost of 4 × 90p or 2 × £1.75)
C1 for correctly choosing small bag from correct working
8 / (a) / 10 × £4.50 / 45 / 2 / M1 for 10 × £4.50
A1 for £45
(b) / 66 ÷ 12 / 5.50 / 2 / M1 for 66 ÷ 12
A1 for £5.50
9 / (a) / 2 correct lines drawn / 2 / B2 for 2 correct lines of symmetry
(B1 for one line of symmetry correct or 2 lines correct and “diagonals” drawn)
(b) / C / 1 / B1 cao
(c) / Shape correctly drawn / 2 / B2 for shape with 3 lines of symmetry and rotational symmetry
(B1 for shape with 3 lines of symmetry or rotational symmetry)
10 / (a) / Correct pattern / 1 / B1 for correct pattern drawn
(b) / 18
22
42 / 4 / B1 for 18
B1 ft for 22
M1 for attempt to count on to get to 10th term
A1 for 42
(c) / No, with reason / 2 / B2 for no with complete reason e.g. all terms in the series are even numbers and 99 is odd)
(B1 for no with partial reason e.g. terms are even)
(d) / 4n + 2 / 2 / B2 for 4n + 2
(B1 for linear expression in 4n e.g. 4n + 1 or attempt at common difference method leading to linear expression in 4n)
Question / Working / Answer / Mark / Notes
11 / (a) / 4.5 × 4.5 / 20.25 / 2 / M1 for multiplying 45 × 45 with place values correct
A1 cao
(b)(i) / 412 / 1 / B1 cao
(b)(ii) / 415 / 1 / B1 cao
12 / 360 –(120 +72 + 95) =
360 – 287 = 73º
180 – 73 = / 107 / 3 / M1 for complete method to find the missing angle of the quadrilateral or sight of 360 – (120 + 72 + 95) or 73
M1 for 180 – “73”
A1 for 107
13 / 120, 240, 360, 480, 600, …
100, 200, 300, 400, 500, 600, …
600 seconds = 10 minutes
4pm + 10 minutes = / 4 10 pm / 4 / M1 for attempt to find the LCM by counting on 120 and 100 or using factors
A1 for 600
M1 for “600” ÷ 60 or sight of 10 minutes
A1 for 4 10 pm
14 / / / 3 / M1 for attempt to add the two fractions by finding a common denominator with one correct
M1 for attempt their fraction from 1 or to add on a fraction to their fraction to get 1
A1 cao
15 / 360 ÷ 12 × 240 ÷ 15 = 30 × 16 = 480
210 ÷ 12 × 240 ÷ 15 = 17.5 × 16 = 280
480 + 280 = 760
760 ÷ 40 = 19 / 19 / 6 / M1 for attempt to find the number of tiles needed for one length or attempt to find the area of one area
M1 for attempt the find the number of tiles needed to cover one wall
M1 for attempt to find the number of tiles needed to cover both walls
A1 for obtaining 30, 16, 17.5 (accept 18) or 16
M1 for dividing “760” by 40
C1 for 19 but accept 20 if 18 is used for 210 ÷ 12 or if an extra box is used in case of breakages

Paper: 5MB2F_01 7

Session: Practice Paper B